1. Field of the Invention
The present invention relates to semiconductor fabrication. More specifically, the present invention relates to formulations and methods for cleaning a substrate surface, and more specifically, for removal of corrosion products from a substrate surface.
2. Description of the Related Art
Semiconductor devices are used in products such as cell phones, radios, televisions, etc. The semiconductor devices include integrated circuits that are connected by conductive wires embedded in insulating material. With the reduction of semiconductor device size and the use of low dielectric constant (low k) interlayer dielectric (ILD) insulating materials, obtaining reliable semiconductor devices is becoming more and more challenging. In particular, reliability problems occur at interfaces of the copper (Cu) wires and low k ILD material in the form of leakage, electromigration, stress migration, break down voltage, and time dependent dielectric breakdown (TDDB), etc.
The dielectric layers are subject to surface contamination during the manufacturing process (e.g., Cu chemical mechanical polishing (CMP) or electroless plating of a metallic capping layer, such as cobalt tungsten phosphorous (CoWP)). These contaminants are charged and mobile, especially under stress, such as high temperature and electric field. The mobility of these contaminants can cause high leakage currents, and may cause damage to the dielectric materials when they move along the interface.
Electroless plated caps can be used in electronic devices to improve the electromigration and stress-migration properties of metallization structures. Electroless deposition processes are wet chemical processes. Such processes are often used with wet cleaning processes to clean the substrates. Although liquid solutions are known for numerous cleaning applications, the present inventors have recognized a need for new and/or improved cleaning solution formulations and methods suitable to clean substrates for the manufacture of electronic devices.
It is in this context that embodiments of the invention arise.